This disclosure relates to analog-to-digital converter arrangement in which an analog signal is converted into a digital signal, and to corresponding methods.
In many applications, analog signals such as analog signals delivered by a sensor, are converted into digital signals and then be processed digitally. A dynamic range of an implemented analog-to-digital converter (A/D) converter may be designed, for example, to handle a maximum value range of an input signal, whereby signal levels associated with the A/D have an optimized signal-to-noise ratio (SNR).
In some applications, however, it is not necessary that the SNR is correlated with an increasing signal level. This is the case, for example, in some applications, such as microphones that are used as signal sources for analog signals. In some applications associated with microphones, certain noise levels exhibit an SNR that stays the same or decreases, without incurring problems at some future time when signals are used. In such applications, adapting an appropriate A/D converter to the maximum range of values with a corresponding curve of the SNR is achieved only with considerable overhead. Such overhead includes having to use an A/D that requires significant implementation area and creates large power dissipation. Furthermore, it may be difficult to provide an appropriate A/D converter for some applications, for example, for microphones having high sound levels, for example, sound levels up to 140 dB sound pressure level (SPL).
Therefore, it may be desirable to provide A/D arrangements and corresponding methods, which enable for example, efficient analog-to-digital conversion of analog signals, such as microphone signals, with a reduced overhead.